From Google's Docs I learned almost everything I need to know on how to use "list_name" with product info. Two things I'm unclear on and looking for best case practices:
1) Should the list name include the page it's on, such as "Home Page Books" for the home page, and then on the book category page "Books Page Books"? Or should both just be called "Books" (because it's the same list just on different pages)??? Maybe the GA reports already add the "appearing on" url data to the list data, so the first way would just look strange, be redundant, and segment something that shouldn't be segmented??? Or maybe the intent is each list is unique and gets its own name??? So maybe you have a "Home Page Search" list for the search feature on the home page, and a "Blog Page Search" list for the search feature on the blog index page??? Or maybe GA intends you to only have one "Search" list that describes the search functionality no matter what page it's on, and GA automatically adds in the url/page data so you can segment by page?????
2) I'm a little fuzzy on what a "list" is defined as, thus where to, and where NOT to use this. If it's a page listing a "red widget", "blue widget", and a "green widget" it's a "Widget" list and everything makes sense. But as an example, what if it's a text link in the body of your homepage text for a "paid consultation"? To me, that seems like a "product impression" just like with the widgets, so you'd want to record that data. So with that assumption, would I use a list_name of "Paid Consultation" and set it up as a list of one item??? I guess what I'm unclear on, does Google intend a "list" as literally a list of multiple products of the same kind, and they don't consider a single product text link as part of a list" -OR- is "list" a clumsy name used because they could come up with anything better and the intent of their system is that anytime you mention a product, whether in a nice grid of multiple products, or as a lone text link on the page, you register the product impression. Or to ask this another way: Is Google's intent for this feature "showing how different products in a category compeat", or rather to record every time you mention any product anywhere on your website???
From looking at the Google Analytics Demo Account Data...
Product List Name is generic, and should be the same for multiple pages. As an example "Search Results" would be a list name for any page that has a search results list. This data can be segmented by "page" by using the "Secondary dimension" button from inside the report under "Conversions" -> "Ecommerce" -> "Product List Performance".
The intent with a "list" at the most basic level, is to measure product impressions. Think of this like answering the question: How many times did I show this product to the user before they clicked on it? For products mentioned as a link inside page text, I'm using the list name of "Text Link".